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by MyOutfitIsVague 173 days ago
Green is in the center of the visible spectrum of light (notice the G in the middle of ROYGBIV), so evolution should theoretically optimize for green light absorption. An interesting article on why plants typically reflect that wavelength and absorb the others: https://en.wikipedia.org/wiki/Purple_Earth_hypothesis
1 comments
bmitc 173 days ago
Green is the highest energy light emitted by our sun, from any part of the entire light spectrum, which is why green appears in the middle of the visible spectrum. The visible spectrum basically exists because we "grew up" with a sun that blasts that frequency range more than any other part of the light spectrum.
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imoverclocked 173 days ago
I have to wonder what our planet would look like if the spectrum shifts over time. Would plants also shift their reflected light? Would eyes subtly change across species? Of course, there would probably be larger issues at play around having a survivable environment … but still, fun to ponder.
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cycomanic 172 days ago
That comment does not make sense. Do you mean the sun emits it's peak intensity at green (I don't believe that is true either, but at least it would make a physically sensical statement). To clarify why the statement does not make sense, the energy of light is directly proportional to its frequency so saying that green is the highest energy light the sun emits is saying the sun does not emit any light at frequency higher than green, i.e. no blue light no UV... That's obviously not true.
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antonvs 172 days ago
> Do you mean the sun emits its peak intensity at green

That's presumably what they mean. It's more or less true, except the color in question is at the green / yellow transition.

See e.g. https://s3-us-west-2.amazonaws.com/courses-images-archive-re...

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bmitc 172 days ago
> Do you mean the sun emits it's peak intensity at green (I don't believe that is true either, but at least it would make a physically sensical statement).

Yes, that's what I meant, as I was sloppy with my language, and it's definitely true.

https://www.sciencedirect.com/topics/physics-and-astronomy/s...

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